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000 
FXUS61 KOKX 180819
AFDOKX

Area Forecast Discussion
National Weather Service New York NY
419 AM EDT Wed Sep 18 2019

.SYNOPSIS...
High pressure will dominate the weather pattern through the 
weekend. A cold front may cross the region early next week.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
Canadian high pressure builds over New England today. NE flow 
around the high has been advecting low level moisture from the 
Atlantic towards the area. There is also shortwave energy diving
south around an upper trough over the Western Atlantic. The 
main challenge for today will be the degree of cloud cover. The 
low level moisture likely gets trapped beneath a subsidence 
inversion around 4-5 kft, especially across portions of Long 
Island and southeast Connecticut. SCT-BKN stratocu
develops/spreads southwestward in the morning and could persist
through around 18z. HRRR and RAP forecast soundings indicate 
the moisture diminishes in the afternoon, but the GFS and NAM 
are a bit slower with this idea. The shortwave energy shifts 
south late in the day. This should help clear any of the 
remaining SCT-BKN clouds with mostly clear conditions by early 
evening. 

High temperatures today will be a few degrees below normal in the 
upper 60s to lower 70s. 

There is a high risk of rip currents at Atlantic Ocean beaches due 
to long period swells from distant Hurricane Humberto.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM THURSDAY/...
Skies will continue to clear tonight as the high pressure slowly 
builds over the Tri-State. A weak pressure gradient remains in 
place near the coast, so winds may not fully decouple here. 
Otherwise, good radiational cooling conditions are forecast 
resulting in temperatures dropping into the lower to middle 40s.
The rest of the area will see lows in the upper 40s and lower 
50s. 

Ridging continues to build aloft on Thursday as western Atlantic 
troughing continues to amplify. Surface high pressure will lie over 
the region with mostly clear skies and temperatures in the upper 60s 
to lower 70s. 

There is a high risk of rip currents at Atlantic Ocean beaches 
on Thursday due to long period swells from distant Hurricane 
Humberto.

&&

.LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/...
Large upper level ridge across the Eastern US will keep the extended 
period dry through the weekend. High pressure at the surface will 
result in plenty of sunshine, light winds and warmer than normal 
temperatures.

With a dry airmass in place, and light winds overnight lows 
Thursday into Friday morning will drop into the 40s for the 
interior and in the Pine Barrens of Long Island with coastal 
locations remaining in the 50s. With better mixing in place on 
Friday, highs will rise into the 70s to near 80.

High pressure will slowly slide off the southeast coast on Saturday, 
allowing winds to turn more southwesterly. This will allow for 
temperatures rise higher through the weekend. These highs will be 10-
12 degrees above normal for this time of the year. 

Hurricane Humberto is forecast to slowly continue tracking northeast 
through the weekend. Indirect impacts will include dangerous rip 
currents and rough surf at Atlantic Ocean beaches. There is 
potential for high surf of 5 to 8 feet Thursday night into 
Friday as swells arrive. Refer to the National Hurricane Center 
for official forecast information on Humberto. Conditions at the
beaches should improve by late Saturday.

The next chance of precipitation will be on Monday and Monday night 
associated with an approaching cold front. High pressure will follow 
behind the frontal passage for Tuesday.

&&

.AVIATION /08Z WEDNESDAY THROUGH SUNDAY/...
VFR through the TAF period as high pressure continues to build 
in from the north today and Hurricane Huberto tracks well 
offshore over the western Atlantic. This will keep the area 
under a prolonged period of north to northeast flow.

Winds will generally be NE through the forecast period. Wind
speeds will be under 10 kt overnight, then the NE flow 
increases to 10 to 15 kt this morning, closer to 15 kt along 
the coast. Gusts 15 to 20 kt develop this morning with 
occasional higher gusts possible, especially this afternoon.

...NY Metro Enhanced Aviation Weather Support...

Detailed information, including hourly TAF wind component fcsts,
can be found at: 
http://www.weather.gov/zny/n90

KJFK TAF Comments: No unscheduled amendments expected.

The afternoon KJFK haze potential forecast is GREEN, which implies
slant range visibility P6SM outside of cloud.

KLGA TAF Comments: No unscheduled amendments expected.

The afternoon KLGA haze potential forecast is GREEN, which implies
slant range visibility P6SM outside of cloud.

KEWR TAF Comments: No unscheduled amendments expected.

The afternoon KEWR haze potential forecast is GREEN, which implies
slant range visibility P6SM outside of cloud.

KTEB TAF Comments: No unscheduled amendments expected.

KHPN TAF Comments: No unscheduled amendments.

KISP TAF Comments: No unscheduled amendments expected.

.OUTLOOK FOR 06Z THURSDAY THROUGH SUNDAY...
.Wednesday night through Sunday...VFR.

&&

.MARINE...
SCA on the ocean waters through Thursday night. 

Seas will continue to build today to 5-7 ft and these seas should 
continue into at least Thursday night in response to long period 
swells from distant Hurricane Humberto. In addition, wind gusts 
could be around 25 kt this afternoon and evening offshore on the 
ocean waters. Otherwise, winds will fall below SCA levels into 
Thursday night. 

Winds will remain below SCA levels through Sunday. Rough seas will 
continue into Friday, and possibly Saturday as long period
swells continue from Hurricane Humberto. Seas gradually subside
below SCA Saturday into Saturday night.

&&

.HYDROLOGY...
No significant hydrologic impacts through the weekend.

&&

.EQUIPMENT...
NYC NOAA Weather Radio Station KWO35 (162.55 MHz) remains off
the air.

&&

.OKX WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...High Rip Current Risk through Friday evening for NYZ075-080-
     081-178-179.
NJ...None.
MARINE...Small Craft Advisory until 6 AM EDT Friday for ANZ350-353-355.

&&

$$
SYNOPSIS...CB/DS
NEAR TERM...DS
SHORT TERM...DS
LONG TERM...CB

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